Indian classical music is both elaborate and expressive. Like Western classical music, it divides the octave into 12 semitones of which the 7 basic notes are, in ascending tonal order, Sa Re Ga Ma Pa Dha Ni for Hindustani music and Sa Ri Ga Ma Pa Dha Ni for Carnatic music, similar to Western music's Do Re Mi Fa So La Ti . However, Indian music uses just-intonation tuning, unlike most modern Western classical music, which uses the equal-temperament tuning system. Also, unlike modern Western classical music, Indian classical music places great emphasis on improvisation.

Indian classical music is monophonic in nature and based on a single melody line, which is played over a fixed drone. The performance is based melodically on particular ragas and rhythmically on talas. Because of the focus on exploring the raga, performances have traditionally been solo endeavours, but duets are gaining in popularity.

Indian music is traditionally taught via aural methods and, until the 20th century, did not employ notations as the primary media of instruction, understanding, or transmission. The rules of Indian music and compositions themselves are taught from a guru to a shishya, in person. Various Indian music schools follow notations and classifications (see melakarta and thaat); these are generally based on a notation system created by Vishnu Narayan Bhatkhande.

Carnatic music, from South India, tends to be more rhythmically intensive and structured than Hindustani music. Examples of this are the logical classification of ragas into melakarthas, and the use of fixed compositions similar to Western classical music. Carnatic raga elaborations are generally much faster in tempo and shorter than their equivalents in Hindustani music. In addition, accompanists have a much larger role in Carnatic concerts than in Hindustani concerts. Today's typical concert structure was put in place by the vocalist Ariyakudi Ramanuja Iyengar. The opening piece is called a varnam, and is a warm-up for the musicians. A devotion and a request for a blessing follows, then a series of interchanges between ragams (unmetered melody) and thaalams (the ornamentation, equivalent to the jor). This is intermixed with hymns called krithis. The pallavi or theme from the raga then follows. Carnatic pieces also have notated lyrical poems that are reproduced as such, possibly with embellishments and treatments according to the performer's ideology.

Primary themes include worship, descriptions of temples, philosophy, and nayaka-nayika (Sanskrit "hero-heroine") themes. Tyagaraja (1759–1847), Muthuswami Dikshitar (1776–1827) and Syama Sastri (1762–1827) are known as the Trinity of Carnatic music, while Purandara Dasa (1480–1564) is considered the father of Carnatic music.

Hindustani music is mainly found in North India. Khyal and Dhrupad are its two main forms, but there are several other classical and semi-classical forms. There is an amount of foreign influences in Hindustani music in terms of the instruments, style of presentation, and ragas such as Hijaz Bhairav, Bhairavi, Bahar, and Yaman. Also, as is the case with Carnatic music, Hindustani music has assimilated various folk tunes. For example, ragas such as Kafi and Jaijaiwanti are based on folk tunes. Players of the tabla, a type of drum, usually keep the rhythm, an indicator of time in Hindustani music. Another common instrument is the stringedtanpura, which is played at a steady tone (a drone) throughout the performance of the raga, and which provides both a point of reference for the musician and a background against which the music stands out. The task of playing the tanpura traditionally falls to a student of the soloist. Other instruments for accompaniment include the sarangi and the harmonium.

The performance usually begins with a slow elaboration of the raga, known as alap. This may be very short (less than a minute) or up to 30 minutes depending on the preference of the musician. In vocal music, the alap is followed by a bandish, generally accompanied by the tabla, around which the raga is improvised. In the case of instrumental music, the alaap could be followed by a more rhythmical piece known as "jod" in which the artist provides rhythm with no rhythmic cycle, and subsequently a piece in fast tempo called ""jhala". The counterpart of the bandish in instrumental music is known as the "gat". The bandish or gat is initially sung or played in slow tempo known as "vilambit laya" to be followed by medium tempo known as "madhya laya" which in turn may be followed by a composition in fast tempo known as pop.

Among the southern classical musicians, U. Srinivas is known for his introduction of the mandolin to Carnatic classical music. Other well established Carnatic instrumentalists are Lalgudi Jayaraman, the late Kunnakudi Vaidyanathan, T.N. Krishnan, L. Subramaniam, M.S. Gopalakrishnan, and the duo of Dr. Mysore Manjunath and Mysore Nagaraj, Kumaresh and Ganesh, all known for their violin performances, veena established artists are E.Gayathri, Jayanthi kumaresh, Veena Srivani Yalla

An emergent trend of the past few decades has been that of fusion music, where genres such as khyal and western music are intermixed to appeal to a wider audience. Pandit Ravi Shankar was one of the earliest to have collaborated with western musicians.[6]

A few of the organizations that promote classical music include Saptak, Sangeet Sankalp,[7] which was established in 1989[8] and SPIC MACAY, which was established in 1977 and has more than 500 chapters in India and abroad.[9][10] SPIC MACAY claims to hold around 5000 events every year related to Indian classical music and dance.